KR20190097232A - Metrology tools and how to use them - Google Patents

Abstract

Subsequent to the first device lithography step of the device patterning process, measuring a degraded metrology mark on the object and / or a device pattern feature associated with the degraded metrology mark, wherein the degraded metrology mark is at least partially applied to the object. Originating from said first device lithography step for; And prior to the second device lithography step of the device patterning process for the object, generating a replacement metrology mark on the object for use in the patterning process instead of the degraded metrology mark.

Description

Metrology tools and how to use them

Cross Reference to Related Application

This application claims the priority of US Provisional Patent Application No. 62 / 439,675, filed December 28, 2016, which is incorporated herein by reference in its entirety.

The present invention generally relates to measuring objects in a manufacturing flow, such as substrates in a semiconductor manufacturing process.

Lithographic apparatus can be used, for example, in the manufacture of integrated circuits (ICs). In this case, the patterning device (eg, mask) includes or provides a device pattern ("design layout") corresponding to each layer of the IC, such pattern as irradiating the target portion through the pattern of the patterning device. In a manner, it can be transferred onto a target portion (including one or more dies) on a substrate (eg, a silicon wafer) coated with a layer of radiation-sensitive material (“resist”). In general, a single substrate includes a plurality of adjacent target portions to which the pattern is successively transferred by the lithographic apparatus one target portion at a time. In one type of lithographic apparatus, the pattern of the entire patterning device is transferred onto one target portion at a time, which apparatus is generally called a stepper. In another apparatus, commonly referred to as a step-and-scan apparatus, the projection beam scans over the patterning device in a given reference direction ("scanning" direction) while moving the substrate in parallel or anti-parallel with respect to the reference direction. Different portions of the pattern of the patterning device are gradually transferred to one target portion. In general, since the lithographic apparatus will have an enlargement factor M (generally <1), the speed F at which the substrate is moved will be multiplied by the speed at which the projection beam scans the patterning device.

Prior to transferring the pattern from the patterning device to the substrate, the substrate may be subjected to various procedures such as resist coating and soft bake. After exposure, the substrate may go through other procedures such as post-exposure bake (PEB), development, hard bake, and measurement / inspection of the transferred pattern. This array of procedures is used as the basis for fabricating each layer of a device, for example an IC. The substrate may then go through a variety of processes, such as etching, ion-implantation (doping), metallization, oxidation, chemical-mechanical polishing, etc., all for finishing each layer of the device. If several layers are needed in the device, the entire procedure, or a variant thereof, is repeated for each layer. Eventually, the device will be in each target portion on the substrate. These devices can then be separated from each other by techniques such as dicing or sawing, and a process such as mounting on a carrier, connecting to a pin, etc., can be performed on each of the devices.

Thus, manufacturing a device, such as a semiconductor device, typically involves processing a substrate (eg, a semiconductor wafer) using various fabrication processes to form various features and multiple layers of the device. Such layers and features are typically fabricated and processed using, for example, deposition, lithography, etching, chemical-mechanical polishing, and ion implantation. Multiple devices may be fabricated over a plurality of die on a substrate and then divided into individual devices. Such a device fabrication process can be considered a patterning process. The patterning process comprises patterning steps such as optical and / or nanoinjection lithography using a patterning device in a lithographic apparatus for transferring a pattern of the patterning device onto a substrate, and typically, but optionally, resist development by a developing apparatus, a baking tool. One or more related pattern processing steps, such as baking of a used substrate, etching using a pattern performed using an etching apparatus, and the like.

As mentioned above, the patterning process for the object may involve transferring one or more patterns to the object, for example a photoresist on the substrate. Effective pattern transfer involves positioning an object prior to pattern transfer. Positioning the object may involve determining the lateral and / or rotational position of the object to accommodate the pattern for pattern transfer. For example, to improve patterning accuracy and improve device yield, it is desirable to improve object alignment. Similarly, other metrology (eg, overlay, critical dimension (CD), patterning beam dose, focus for optical exposure, etc.) can be used in the patterning process, thus improving patterning accuracy and improving device yield, for example. It is desirable to improve these measurements to improve.

In one embodiment, subsequent to the first device lithography step of the device patterning process, measuring the degraded metrology mark on the object and / or device pattern feature associated with the degraded metrology mark, wherein the degraded metrology mark is at least partially As a result from the first device lithography step for the object; And before the second device lithography step of the device patterning process for the object, generating a replacement metrology mark on the object for use in the patterning process instead of the degraded metrology mark. Is provided.

In one embodiment, a metrology sensor configured to measure a degraded metrology mark on an object following a first device lithography step of a device patterning process and / or to measure a device pattern feature associated with the degraded metrology mark—the degradation A metrology mark is at least in part resulting from the first device lithography step for the object; And a mark appending device configured to generate a replacement metrology mark on the object prior to any subsequent device lithography step of the device patterning process, wherein the replacement mark is to be used in the patterning process instead of the degraded metrology mark. An apparatus is provided, including.

In one embodiment, a first metrology sensor is configured to measure a degraded metrology mark on the object in accordance with a first type of mark metrology; A mark adding device configured to add a replacement metrology mark on the object based on the measurement of the deteriorated mark; And a second measurement sensor configured to measure the replacement measurement mark in accordance with a second type of mark measurement different from the first type of mark measurement.

These and other features of the present invention, as well as methods and functions of operations and functions of manufacturing associated components of structures and combinations of parts, will become apparent from consideration of the following description and the appended claims with reference to the accompanying drawings, all of which Form part of this specification, like reference numerals designating corresponding parts in the various figures. However, it should be clearly understood that the drawings are for illustration and description only and are not intended to define the limits of the invention. As used in this specification and in the claims, the singular forms “a,” “an,” and “the” include plural reference members unless the context clearly indicates otherwise. Also, as used in the specification and claims, the term "or" means "and / or" unless the context clearly indicates otherwise.

Embodiments are illustrated in the accompanying drawings by way of example and not by way of limitation, in which like reference numerals indicate similar components.
1 shows a schematic diagram of one embodiment of a lithographic apparatus;
2 shows a schematic diagram of one embodiment of a lithographic cell;
3A-3C schematically depict schematic diagrams of exemplary metrology marks on an object during a patterning process, according to one embodiment;
4 schematically illustrates a metrology mark module configured to detect metrology marks on an object and provide metrology marks on an object, according to one embodiment;
5A-5D schematically illustrate cross-sectional views of an object with metrology marks and additional metrology marks, according to one embodiment;
6 is a flowchart of a processing method according to an example; And
7 shows a block diagram of an example computer system.

1 schematically depicts a lithographic apparatus LA in which the techniques described herein may be utilized. Such devices include an illumination optical system (IL) configured to regulate a radiation beam B (eg, ultraviolet (UV), deep ultraviolet (DUV) or extreme ultraviolet (EUV) radiation); A patterning device support or support structure (e.g., connected to a first positioner PM configured to support a patterning device (e.g., a mask MA and configured to accurately position the patterning device according to certain parameters) A mask table MT, one connected to a second positioner PW configured to hold a substrate (e.g., a resist-coated wafer W and configured to accurately position the substrate according to specific parameters) The above-described substrate table (for example, wafer tables WTa and WTb); and the pattern imparted to the radiation beam B by the patterning device MA to the target portion C of the substrate W (for example, A projection optical system (eg, refractive, reflective, reflective refractive system) PS configured to project onto one or more dies.

The illumination optical system may be of various types of optical components for directing, shaping, or controlling radiation, such as refractive, reflective, magnetic, electromagnetic, electrostatic or other types of optical components, or any of these. Combinations may also be included. In this particular case, the illumination system further comprises a radiation source SO.

The patterning device support holds the patterning device in a manner that depends on the orientation of the patterning device, the design of the lithographic apparatus, and other conditions, such as for example whether the patterning device is maintained in a vacuum environment. The patterning device support can use mechanical, vacuum, electrostatic, or other clamping techniques to hold the patterning device. The patterning device support may be, for example, a frame or table that can be fixed or moved as required. The patterning device support may ensure that the patterning device is in a desired position, for example with respect to the projection system. All uses of the term "reticle" or "mask" herein may be considered synonymous with the more general term "patterning device".

The term "patterning device" as used herein is broadly interpreted as referring to any device that can be used to impart a beam of radiation having a pattern in its cross section, such as creating a pattern in a target portion of a substrate. Should be. The pattern imparted to the radiation beam may not exactly match the required pattern at the target portion of the substrate, for example if the pattern comprises a phase shifting feature or a so-called assist feature. Care must be taken. In general, the pattern imparted to the radiation beam will correspond to a particular functional layer in a target portion, such as a device being created in an integrated circuit.

The patterning device can be transmissive or reflective. Examples of patterning devices include masks, programmable mirror arrays, and programmable (LCD) panels. Masks are well known in the lithography art and include mask types such as binary, alternating phase-shift, attenuated phase-shift, and various hybrid mask types. One example of a programmable mirror array employs a matrix alignment of small mirrors, each of which may be individually tilted to reflect incoming radiation beams in different directions. The tilted mirror imparts a pattern in the radiation beam reflected by the mirror matrix. As another example, the patterning device includes an LCD matrix.

As shown, the apparatus is transmissive (e.g., employing a transmissive patterning device). However, the device may be of a reflective type (e.g., employing a programmable mirror array of a type as mentioned above, or employing a reflective mask (e.g. for EUV systems)).

The lithographic apparatus may also be of a type such that at least a portion of the substrate may be covered by a liquid, such as water, having a relatively high refractive index to fill the space between the projection system and the substrate. Immersion liquids may also be applied to other spaces in the lithographic apparatus, for example, between the mask and the projection system. Immersion techniques are well known in the art to increase the numerical aperture of projection systems. The term “immersion” as used herein does not mean that a structure, such as a substrate, must be submerged in liquid, but rather means that liquid is located between the projection system and the substrate during exposure.

Referring to FIG. 1, illuminator IL receives a radiation beam from a radiation source SO (eg, a mercury lamp or excimer laser, an LPP (laser generated plasma) EUV source). For example, if the source is an excimer laser, the source and lithographic apparatus may be separate entities. In this case, the source is not considered to form part of the lithographic apparatus and the radiation beam is, for example, with the aid of a beam delivery system BD comprising a suitable directional mirror and / or beam expander, source SO. From the illuminator IL. In other cases, such as when the source is a mercury lamp, this source may be a component integrated in the lithographic apparatus. The source SO and the illuminator IL may be referred to as a radiation system together with the beam delivery system BD if necessary.

The illuminator IL may comprise an adjuster AD for adjusting the spatial and / or angular intensity distribution of the radiation beam. In general, at least the outer and / or inner radial range of the intensity distribution in the pupil plane of the illuminator IL (commonly referred to as outer-σ and inner-σ, respectively) can be adjusted. In addition, illuminator IL may include various other components such as an integrator (IN) and a condenser (CO). The illuminator can be used to adjust the radiation beam to have the desired uniformity and intensity distribution in its cross section.

The radiation beam B is incident on the patterning device (e.g. mask MA) held on the patterning device support (e.g. mask table MT) and patterned by the patterning device. Crossing the patterning device (e.g. mask MA), the radiation beam B passes through a projection optical system PS which focuses the beam on the target portion C of the substrate W, thereby producing an image of the pattern. Is projected onto the target portion (C). With the help of a second positioner PW and a position sensor IF (e.g., an interferometric measuring device, a linear encoder, a 2-D encoder or a capacitive sensor), for example, of the radiation beam B In order to position different target portions C in the path, the substrate table WT can be moved accurately. Similarly, the first positioner PM and other position sensors (not clearly depicted in FIG. 1) may be used, for example, after mechanical search from the mask library, or during scanning, of the radiation beam B. A patterning device (eg, mask MA) can be used to accurately position the path.

The patterning device (eg mask MA and substrate W) can be aligned using patterning device alignment marks M ₁ , M ₂ and substrate alignment marks P ₁ , P ₂ . Likewise, substrate alignment marks occupy dedicated target portions, but they may be located in the space between the target portions (these are known as scribe-lane alignment marks.) Similarly, in the patterning device (eg mask MA) In situations where two or more dies are provided, patterning device alignment marks may be located between the dies, small alignment markers may also be included in the die and between the device features, in which case the markers are as small as possible. It is desirable not to require any other imaging or process conditions relative to adjacent features. It is.

In this example the lithographic apparatus LA is of a so-called dual stage type, having two substrate tables WTa, WTb and two stations, an exposure station and a measuring station, between which the substrate tables can be exchanged. While one substrate in one substrate table is exposed at the exposure station, the other substrate can be loaded into another substrate table at the measurement station, and various preparatory steps can be performed. The preparatory step is to map the surface control of the substrate using the level sensor LS, to measure the position of the alignment marker on the substrate using the alignment sensor AS, to perform any other type of measurement or inspection. And the like. This can greatly increase the throughput of the lithographic apparatus. More generally, the lithographic apparatus may be of a type having two or more tables (eg, two or more substrate tables, one substrate table and one measurement table, two or more patterning device tables, etc.). In such a "multi-stage" device, multiple of the plurality of tables may be used in parallel, and preparatory steps may be performed on one or more tables while one or more other tables are being used for exposure. Twin stage lithographic apparatus are described, for example, in US Pat. No. 5,969,441, the entire contents of which are incorporated herein by reference.

Although the level sensor LS and the alignment sensor AS are shown adjacent to the substrate table WTb, additionally or alternatively, the level sensor LS and the alignment sensor AS are measured in relation to the substrate table WTa. May be provided adjacent to the projection system PS.

The depicted apparatus can be used in various modes, including, for example, step mode or scan mode. The structure and operation of the lithographic apparatus are well known to those skilled in the art and need not be further described for the understanding of embodiments of the present invention.

As shown in FIG. 2, the lithographic apparatus LA forms part of a lithographic system, called a lithographic cell LC or lithocell or cluster. The lithographic cell LC may further comprise an apparatus for performing pre-exposure and post-exposure processes on the substrate. Typically, such a device is a spin coater (SC) for depositing a resist layer, a developer (DE) for developing the exposed resist, a chill plate (CH), and a bake plate (BK). ). The substrate handler or robot RO picks up the substrates from the input / output ports I / O1, I / O2, moves them between different process apparatuses, and then transfers them to the loading bays of the lithographic apparatus. do. These devices, collectively referred to as tracks, are under the control of a track control unit (TCU) controlled by a supervisory control system (SCS), which is also lithographically controlled via a lithography control unit (LACU). To control the device. Therefore, different devices can be operated to maximize throughput and processing efficiency.

In the patterning process, one or more alignment marks (eg, substrate alignment marks P ₁ , P ₂ ) induce the pattern to be placed over the substrate W. In one embodiment of a patterning process (eg, an integrated circuit fabrication process), the alignment sensor AS (eg, combined with the position sensor IF) is a substrate W (eg, a semiconductor wafer). The position of one or more alignment marks on the image is determined, and the position of the substrate is adjusted relative to the patterning device MA according to the determined position of the alignment marks before pattern transfer in the lithographic apparatus. If a misalignment occurs in a pattern in a device (eg an integrated circuit), the device may fail or performance may deteriorate and / or the yield of the device obtained from the substrate W may drop. For example, if a misaligned interconnection occurs due to an error in the pattern placement, the interconnect area at the metal interconnect can be reduced and thus the electrical resistance within the device can be increased. Therefore, improving the pattern alignment of the elements of the device can reduce manufacturing defects during the patterning process and increase the device yield obtained from the substrate W.

Similarly, one or more other metrology marks (eg, used to determine overlay, CD, focus, dose, etc.) may also degrade. Thus, their measurement results may also give inaccurate results, and consequently, if such results are used to control the patterning process, the device may fail or degrade performance and / or devices obtained from the substrate W Yield may drop.

In one embodiment, one or more metrology marks (eg, alignment marks) are formed on the object (eg, substrate W). In one embodiment, one or more metrology marks are formed by creating a metrology mark pattern in a layer of resist on an object. In one embodiment, the metrology mark pattern in the resist is transferred to a material located under the resist. Etching may include plasma etching and / or wet chemical etching treatment of the film in the stack of material on the object. In one embodiment, one or more metrology marks are formed at least in the topmost non-resist layer of the object and remain in the topmost non-resist layer of the object after etching.

In one embodiment, one or more patterning process steps subsequent to forming metrology marks in the object, followed by the next pattern transfer step for the object, degrade the metrology marks. For example, the metrology mark may be degraded by chemical mechanical polishing (CMP) of the object, for example, a part of the metrology mark may be lost, or at least part of the shape of the metrology mark may be deformed. In one embodiment, the deformation of the measurement mark shape refers to the formation of a wavy line rather than a straight curve of the measurement mark or a straight line of the measurement mark. In one embodiment, degradation of metrology marks includes damage, distortion, and / or shielding of metrology marks. In one embodiment, the degraded mark includes metrology marks that are incompatible with the metrology system of a particular lithocell (eg, the degraded mark may be designed for use with a metrology system obtained from one vendor, and the other Incompatible with measurement systems obtained from vendors). Relying on deteriorated metrology marks, the metrology step takes, for example, more time, less accuracy, and / or less reproducibility. In one embodiment, the damaged, distorted, and / or shielded degraded metrology mark is the result of the patterning process, e.g., transfer of the pattern to a previously provided pattern (eg, at a lower level) on the object. It will cause misalignment.

Metrology marks may not be suitable for measurements using certain types of metrology. For example, in one embodiment, when used in a lithocell, the first type of mark metrology is selected for one or more performance factors such as mark detection speed and / or mark detection accuracy. In one embodiment, the first type of mark metrology may not be suitable for detecting degraded metrology marks. In one embodiment, the first type of mark metrology includes a diffraction-based mark detection system.

Therefore, in one embodiment, after detecting the degraded measurement mark using the second type of mark measurement, a replacement measurement mark (e.g., a new replacement measurement mark, a repair of the measurement mark, Alignment tools (e.g., alignment of lithographic cells (e.g., lithographic apparatuses) used to generate enhanced metrology marks (i.e., marks that differ in design from the original metrology marks and typically have better performance than the original). A tool or module separate from the sensor) is provided. Therefore, the object (having deteriorated measurement marks) can still be processed using the first type of mark measurement by using the first type of mark measurement to detect the replacement measurement mark on the object. The second type of mark metrology can be used, for example, to determine whether the degraded metrology mark is degraded and / or to enable determination of the offset (if present) between the degraded replacement mark and the replacement metrology mark.

In one embodiment, instead of generating a replacement metrology mark, an offset for an existing degraded metrology mark may be determined through measurement of the degraded metrology mark by the second type of mark metrology. This can be done, for example, if the degraded metrology mark is of sufficient quality for measurement using the mark measurement of the first type of lithocell. The offset provides a measure of the amount of error at the location, measured using degraded metrology marks. The offset can thus provide a position correction as to when the degraded metrology mark is measured using the first type of mark metrology.

In one embodiment, the second type of mark metrology may not be suitable for use in the lithocell, for example because of the slower measurement speed for the first type of mark metrology. However, the second type of mark measurement is suitable for detecting deteriorated measurement marks on the object.

In one embodiment, the second type of mark metrology is an optical method using non-visible radiation such as infrared radiation, ultraviolet radiation, and / or x-ray radiation. In one embodiment, the second type of mark metrology is atomic force microscopy (AFM). In one embodiment, the second type of mark metrology employs visible light, but employs visible light having a different visible range than that for the first type of mark metrology (ie, using near field or other optical microscopy).

In one embodiment, the second type of mark metrology is a stack metrology that takes into account the effect of one or more layers overlying metrology marks or portions thereof, such one or more layers being such as when measuring a "true" position. This makes the measurement with the measurement mark inaccurate. For example, stack metrology may include an apparent transition (re-weighting) in the wavelength distribution due to one or more layers and / or an apparent transition (reweighting) in the numerical aperture distribution due to one or more layers. ) Can be determined. In one embodiment, the measured transition relates to reflectivity. Using proper calibration (eg, calibration for one or more reference substrates with a known layer on the metrology mark), the superficial transition can be converted to the position offset of the metrology mark as the metrology mark is measured to determine its location. . Therefore, in one embodiment, similar to other second types of mark metrology, stack metrology determines, for example, whether deteriorated metrology marks are degraded and / or offsets between deteriorated replacement marks and replacement metrology marks. Determination of (if present) can be made possible.

Referring to FIG. 3A, the measurement mark 100 (in this case, the alignment mark) is not degraded, suitable for measurement using a measurement device (eg, alignment sensor AS) using the first type of mark measurement. Not shown schematically in the form of metrology marks. In this example, the metrology mark 100 includes a recessed region 102 (in this case, a plurality of trenches 102), with a ridge 104 between each pair of trenches 102. Each trench 102 has a straight sidewall 106 and a rectangular edge 108 when viewed from above the metrology mark.

Referring to FIG. 3B, the schematic representation of the degraded metrology mark 110, based on the metrology mark 100, is a missing pattern element such that metrology using the first type of metrology is less reliable than that of metrology mark 100. Shows. The degraded metrology mark 110 includes a recessed section 112 and a ridge 114 extending inward toward the center of the recessed section 112. In the degraded metrology mark 110, the ridge 114 was broken and previously isolated trenches were merged into the recessed area 112. The deteriorated measurement mark 110 has a patternless area 116 in which a part of the ridge 114 is separated from the object. The side wall 118 of the degraded metrology pattern 110 is roughly w linear despite the damage to the ridge 114. In one embodiment, the second type of mark metrology may detect and measure deteriorated metrology marks (eg, degree of alignment), such as deteriorated metrology marks 110, for example, because of the second This is because a type of mark metrology (1) has a longer time period to perform mark detection and measurement, and / or (2) employs interaction with different types of radiation and / or metrology marks.

Referring to FIG. 3C, a schematic of metrology mark 120 based on metrology mark 100 is shown below a layer of shielding material over the metrology mark. Trench 122 and ridge 124 with straight sidewalls 126 and rectangular edges 128 are present in the metrology mark. The intervening layer of material (ie, the layer between the metrology mark and the detector) sometimes shields the metrology mark from the type of metrology used in the lithocell, making it more difficult to position the metrology mark. In one embodiment, the metrology mark shielded (ie, difficult or impossible to detect) by the first type of metrology is a second type of metrology that penetrates or goes deeper into the object (eg, one or more layers thereof). Detectable using In one embodiment, a second type of metrology employing non-visible radiation, such as infrared or x-ray radiation, that penetrates into an object (eg, one or more layers thereof) may provide a shielded mark, such as metrology mark 120. Can be detected and measured. The radiation that passes through the object (eg, an intervening layer of material) is redirected differently from the material adjacent and / or surrounding the metrology mark 120 at the location of the metrology mark 120.

Referring to FIG. 4, a schematic diagram of metrology mark module 200 used to detect one or more metrology marks and other features on an object is shown. Metrology mark module 200 includes a peripheral enclosure 202 that holds a frame 204 supported by, for example, vibration isolation system 206 on metrology base 208. In one embodiment, the frame 204 supports the first metrology sensor 224 and / or the optional second metrology sensor 226. In one embodiment, the frame 204 supports the mark printer 228. However, in one embodiment, the mark printer 228 is supported on a separate frame that is mechanically isolated from the frame 204.

Object 210 is supported on stage 212 within frame 204. The position of the stage 212 is measured using the position measuring system 211 (and thus the metrology mark module 200 controls the position of the stage 212 using the output of the position measuring system 211. ). In one embodiment, the positioning system 211 has a grid plate on which the stage 212 is positioned as an encoder system for determining the position of the stage 212 relative to the grid plate 214 within the frame 204. It has a plurality of grid plate readers 216 configured to cooperate with 214. As can be appreciated, grid plate 214 can be provided to the stage, and grid plate reader 216 can be provided to frame 204. Different position measurement systems 211 (eg, interferometers) may be used.

The stage 212 enables determination of the position of the stage 212 relative to one or more portions of the module (eg, the position of the stage 212 relative to the mark printer 228) and / or one on the object. One or more stage alignment markers 218 for use as a reference for determining the position of the metrology marks. For example, the alignment marker 218 may be used to determine a position offset between the first metrology sensor 224 and the mark printer 228, between the first metrology sensor 224, the second metrology sensor 226, and the like. Can be.

The handler 220 receives the object 210 and places it on the stage 212. The level sensor 222 measures the height and / or tilt of the object 210 under the first metrology sensor 224, the optional second metrology sensor 226, and the mark printer 228.

In one embodiment, the first metrology sensor 224 has a degraded metrology mark with higher accuracy than the metrology tool (eg, alignment sensor AS) of the lithocell designed such that the degraded metrology mark is measured in relation. And detect and measure. In one embodiment, the first metrology sensor 224 is configured to be easily replaceable (eg, more easily replaceable than the second metrology sensor 226). The first metrology sensor 224 of different technology and / or performance may be provided in response to the nature of degradation of the metrology mark (eg, degree of damage, presence of intervening layers, etc.). For example, for degraded metrology marks, an appropriate first metrology sensor 224 may be inserted in module 200 with greater sensitivity than first metrology sensor 224. As another example, the first metrology sensor 224 may come from under the object (not shown in FIG. 4 for convenience), passing through the object and detected by the sensor 224 at a position opposite the origin of illumination with respect to the object. It may be. Therefore, in one embodiment, the first metrology sensor 224 is a second type of mark metrology. In one embodiment, the first metrology sensor 224 is an infrared detector, ultraviolet radiation detector, and / or x-ray detector. In one embodiment, the first metrology sensor 224 is an atomic force microscope or near field optical microscope. In one embodiment, first metrology sensor 224 uses electrons or other particles to measure metrology marks. In one embodiment, the metrology mark module 200 displays the degraded metrology marks with a higher accuracy than the metrology tool (eg, alignment sensor AS) of the lithocell designed such that the degraded metrology marks are measured in relation. Each is configured to measure, and in one embodiment includes two or more first metrology sensors 224, each of a different type of measurement (eg, one is infrared while the other is ultraviolet).

The mark printer 228 is configured to generate a replacement metrology mark on the object when there is a degraded metrology mark. In one embodiment, creating the replacement metrology mark involves adding material to the object surface (eg, a layer of material on the object). In one embodiment, the added material is added within module 200 (eg, by object handler 220 and / or mark printer 228). In one embodiment, the material added to generate the replacement metrology mark may be added to either the top side of the object, the bottom of the object, or both the top and bottom side during the mark generation process. In one embodiment, the mark material is deposited directly on the object surface. Some objects have a layer of resist and / or a layer of anti-reflective coating (ARC), in which metrology marks can be created, or metrology marks can be formed thereon using mark material deposited thereon. have.

In one embodiment, the replacement metrology mark may be formed by a subtractive process. In one embodiment, the deduction process uses mark material deposited on the object (eg, specifically deposited for the mark printer 228) to generate a replacement metrology mark, or an existing surface (eg, on the object). For example, a layer of resist) can be used. In one embodiment, an exemplary subtraction process is to expose an unexposed layer of radiation-sensitive material to radiation to change the chemical structure of an optical process, such as a portion of the material, which portion corresponds to a pattern of replacement metrology marks. do. The subsequent development process of the layer of material removes a portion of the layer of material and leaves a pattern corresponding to the replacement metrology mark on the object. In one embodiment, the deduction process is an ablation process that forms a replacement metrology mark by mechanically removing material using radiation.

In one embodiment, the replacement metrology mark may be formed by an additional process. In one embodiment, the mark material added to the object as described above is added in the form of a pattern of replacement metrology marks. In one embodiment, the additional process uses an inkjet-type dispenser to dispose of the added material in the form of a replacement metrology mark pattern.

In one embodiment, the replacement metrology mark can be formed by shaping the material on the object. In one embodiment, the probe tip is moved close to the surface of the material to distort the surface using, for example, van der Waals forces, leaving behind a physically-modified surface behind the probe tip as the probe tip moves across the surface. do. In one embodiment, the material is a resist, for example a developed resist.

In one embodiment, the replacement metrology mark is formed by pressing the mold onto the surface of the material on the object, leaving an impression after the mold is removed from the surface of the layer of material. In one embodiment, the material is a resist, for example a developed resist.

In one embodiment, the mark printer 228 is configured to provide replacement metrology marks, for example, at offsets known relative to degraded metrology marks and / or device pattern features. In one embodiment, the control system of metrology mark module 200 is a degraded metrology mark in the coordinate system of metrology mark module 200, for example in cooperation with first metrology sensor 224 (position measurement system 211). This is made possible by measuring the position of the deteriorated measurement mark using the &quot; In one embodiment, the control system of metrology mark module 200 is configured to, for example, cooperate with a first metrology sensor 224 (position measurement system 211) of the device pattern feature in the coordinate system of metrology mark module 200. This is made possible by measuring the location of device pattern features (eg, important device pattern features that are exposed to defects if the overlay is not accurate and / or important for the device's functionality) using location determination. The control system controls the position of the object 210 relative to the mark printer 228 using the position measuring system 211 so that the mark printer 228 can generate a replacement metrology mark at the corresponding offset.

In one embodiment, the optional second metrology sensor 226 is configured to measure the replacement metrology mark. In one embodiment, the second metrology sensor 226 is different from the first metrology sensor 224. In one embodiment, the second metrology sensor 226 is a diffraction based sensor. In one embodiment, the second metrology sensor is a sensor of the same or similar type as the metrology tool (eg, alignment sensor) of the lithocell whose deteriorated mark is designed for measurement. Therefore, in one embodiment, the second metrology sensor 226 is a first type of mark metrology.

In one embodiment, metrology mark module 200 may enable features additionally or alternatively to replacement mark generation. For example, this can provide tool-tool alignment / overlay matching. That is, in one embodiment, because the metrology mark module 200 has a metrology sensor, this may enable matching of the overlay / alignment between two or more lithographic apparatuses. For example, this can measure the overlay for one lithographic apparatus and similarly measure the overlay from another lithographic apparatus, and determine the offset so that the two lithographic apparatus can create a similar overlay. In one embodiment, metrology mark module 200 may generate an overlay / align fingerprint across the substrate to enable matching.

In one embodiment, metrology mark module 200 may enable calibration of other metrology systems (eg, alignment sensor AS) in the lithocell. For example, this can be used to determine the process variation sensitivity of other metrology systems in the lithocell.

In one embodiment, metrology mark module 200 may provide for rearward metrology of an object without the need for the object to be flipped, or one or more metrology systems in the lithocell do not provide for rearward metrology of the object without flipping the object. Do not.

5A-5D schematically show cross-sectional views of examples of an object having a metrology mark and a replacement metrology mark.

Referring to FIG. 5A, an object 300 having a layer 302 with metrology marks 304 (in one embodiment, the layer 302 is an underlying substrate, such as a silicon wafer) is a layer 302 of the object. Has a replacement metrology mark 306 formed therein and / or has a replacement metrology mark 308 formed on the layer 302 of the object. In one embodiment, the replacement metrology mark 306 is a subtractive mark formed on the top surface of the layer 302. In one embodiment, the replacement metrology mark 308 is an additional mark formed on the top surface of the layer 302.

Referring to FIG. 5B, an object 310 having a layer 312 with metrology marks 314 in layer 312 (in one embodiment, layer 312 is an underlying substrate, such as a silicon wafer), It is shown with replacement metrology marks 316 formed in coating layer 318 on the top surface of layer 312. In one embodiment, coating layer 318 includes a layer of anti-reflective coating (ARC), and / or a layer of resist on layer 312. The replacement metrology mark 316 may be formed by a subtraction process or a molding process.

Referring to FIG. 5C, an object 320 having a layer 322 with metrology marks 304 (in one embodiment, the layer 322 is an underlying substrate, such as a silicon wafer) is a top layer 322 of the object. ) Has a replacement metrology mark 326 formed in the coating layer 324. Coating layer 324 and replacement metrology mark 326 are covered by second coating layer 328. In one embodiment, the coating layer 324 is ARC and the second coating layer 326 is a resist layer for receiving a pattern for the layer of the device.

Referring to FIG. 5D, an object 330 having a layer 332 with coating layers 334 and 335 (in one embodiment, layer 332 is an underlying substrate, such as a silicon wafer) is an object 330. Replacement metrology marks 336 located in backside coating layer 338 on backside 340. As with the replacement metrology marks 306, 316, and 326, replacement metrology marks 336 can be formed by adding or subtracting, or by reshaping the coating layer of material on the object.

6 is a flowchart of an object patterning method according to an embodiment. The method 400 includes an operation 402 in which the metrology mark is inspected with an inspection device. In one embodiment, the metrology mark is measured using a second type of mark metrology as described above (eg, using the first metrology sensor 224). According to some embodiments, the second type of mark metrology includes infrared imaging, visible light imaging, ultraviolet radiation imaging, or x-ray imaging. In one embodiment, the second type of mark metrology includes a form of microscopy, such as atomic force microscopy or near field microscopy. In one embodiment, the second type of mark metrology includes a particle-based detection system. In one embodiment, the image of the metrology mark may be recorded using, for example, the first metrology sensor 224, a camera, or the like.

The method 400 optionally includes an operation 404 in which it is determined whether one or more metrology marks on the object are degraded. In one embodiment, the determination of whether the metrology mark is degraded can be made by evaluating whether the line straightness, the shape of the metrology mark, and / or the feature of the metrology mark has disappeared in the measured image of the metrology mark. In one embodiment, the determination of whether the metrology mark is degraded is determined by analyzing the measurement result of the first metrology sensor 224, for example measured by the first metrology sensor 224 for the expected position of the metrology mark. By determining the relative position. In one embodiment, the determination is a fully automated process that uses a processing algorithm to detect factors related to mark quality, and / or uses processing involving human interaction to confirm the quality of the metrology mark. After performing operation 404, operation 406 is subsequently performed on the object having the degraded metrology mark, while operation 418 is subsequently performed on the object having the metrology mark that has been determined not to degrade. The metrology mark may be treated as if it has degraded, and operation 406 and subsequent operations may be performed on one or more of the metrology marks on the object.

In operation 406, the object undergoes an object mark detection process using a second type of mark measurement (different from the type of mark measurement in the lithocell used to measure the degraded measurement mark). As can be appreciated, the type of mark metrology used within the lithocell or separate metrology mark module 200 is selected according to the parameters associated with using such an apparatus or module in a manufacturing environment. Factors related to selecting one mark metrology in one module include time constraints, mark detection accuracy and / or reproducibility, maintenance and calibration of the metrology device, and the like. Mark metrology used within the lithocell will tend to have shorter measurement and / or analysis times than stand-alone metrology mark modules, such as the second type of metrology used in metrology mark module 200. Marking of the second type used in standalone metrology mark modules, such as metrology mark module 200, has simpler maintenance requirements than metrology used in lithocells that are subject to deteriorated metrology marks to be designed and typically measured and And / or can be replaced more easily (less working time and shorter stabilization time after maintenance).

In one embodiment, operation 406 is performed in a device (or portion of the device) separate from the measurement system of the lithocell for which the degraded alignment mark is designed. Therefore, in one embodiment, operation 406 is performed at a standalone metrology mark module, such as metrology mark module 200 provided in standalone format. In one embodiment, operation 406 is performed in an in-track metrology mark module, such as metrology mark module 200 as part of a track. In one embodiment, operation 406 is a metrology mark module in a portion of the lithographic apparatus that is separate from the measurement apparatus in the lithographic apparatus in which the degraded metrology mark is to be designed and used, for example, as part of a lithographic apparatus separate from the alignment sensor AS. Performed at 200.

The metrology mark module can be configured to have one or more sensors suitable for making other types of metrology in addition to sensors compatible with the second type of mark metrology. In one embodiment, the metrology mark module has multiple stations where metrology takes place in one station and mark repair / replacement occurs in another station, thereby making the slower type of mark metrology in the module, and / or a plurality of different second ones. It may be configured to compensate for the use of the mark measurement of the type.

In one embodiment, the object mark detection process includes determining the position of the degraded metrology mark using the second type of mark metrology and measuring the degraded metrology mark. In one embodiment, the object mark detection process may use the measurement results from operation 402, which involves using a second type of mark measurement. In one embodiment, the object mark detection process may be measured using a metrology system using a second type of mark metrology, such as the first metrology sensor 224.

In operation 408, after a degraded metrology mark is detected, a replacement metrology mark (eg, an enhanced metrology mark, or a new metrology mark) is created on the surface of the object. In one embodiment, the replacement metrology mark is generated at a metrology mark position at a particular offset distance from the position of the degraded metrology mark. As can be appreciated, creating a replacement metrology mark some distance from the position of the degraded metrology mark avoids confusing the feature of the replacement metrology mark with the mark feature of the degraded metrology mark. In one embodiment, replacement metrology marks are generated, for example, at known offsets from degraded metrology marks and / or device pattern features. This, for example, aligns the degraded metrology mark using the first metrology sensor 224 and then provides a replacement metrology mark using the mark printer 228 at a known offset from the first metrology sensor 224. This can be done by. This is for example a mark printer at a known offset from the first metrology sensor 224 after measuring the location of the device pattern feature (eg, critical device pattern feature) using the first metrology sensor 224. By using 228 to provide a replacement metrology mark. Or, in one embodiment, the position of the degraded metrology mark and / or device pattern feature may be determined using the first metrology sensor 224, then alternate metrology using the mark printer 228 at a particular known offset. To provide a mark, relative displacement between the object and the mark printer 228 can be made. In one embodiment, the replacement metrology mark is located directly above the position of the degraded metrology mark (thus zero offset from the degraded metrology mark but to some extent from the device pattern feature).

In one embodiment, if the degraded alignment mark shows reproducibility but the accuracy is inadequate, a replacement metrology mark may not be generated. Then, a correction data record may be generated at operation 408 to allow for better measurements using the first type of measurement system in the lithocell. For example, the data record may include data related to the position error (e.g., the position error of the degraded metrology mark with respect to the device pattern feature, as determined using stack metrology, for example, Can be determined by comparing the position of the degraded metrology mark measured to the device pattern with the known position of the degraded mark relative to the device pattern), etc.), mark structure asymmetry, measurement beam wavelength to be used to measure the degraded metrology mark. Information related to the measurement beam, the measurement beam numerical aperture for measuring the deteriorated measurement mark, or the measurement beam illumination radiation spatial distribution or angular distribution.

In optional operation 410, the replacement metrology mark is measured using a first type of metrology as described above (eg, see second metrology sensor 226 in metrology mark module 200 of FIG. 4). It is measured within the mark module. In one embodiment, the first type of metrology ensures that the replacement metrology mark is readable by a metrology system that is the same as or similar to the metrology tool (eg, alignment sensor) in the lithocell to which the degraded metrology mark is designed. Can be used to help. In one embodiment, the first type of metrology can be used to determine the location of the replacement metrology mark and, for example, to determine the offset between the replacement metrology mark and the degraded metrology mark / device pattern feature. This can be done, for example, by determining the position of the replacement metrology mark relative to a reference (eg, alignment marker 218, device pattern feature, etc.) with a first type of measurement, where the second type of measurement is a degraded measurement. The position of the mark was determined relative to the same reference (or another reference having a known position relative to the reference for the second type of measurement).

The method 400 determines that a correction offset is determined based on the actual measured position of the replacement metrology mark (eg, determined in operation 410), and this is a known offset of the replacement metrology mark (eg, operation ( And optionally 412, which may be combined with (as determined from 408). Thus, if the determination of the offset is improved, the alignment to the object can be improved based on the replacement metrology mark in the lithographic apparatus.

In addition, the method 400 may include, by means of a metrology mark module, a position of the replacement metrology mark and / or an offset with respect to the replacement metrology mark (this may be, for example, a known offset, a combination of known and corrected offsets, measured offset May optionally include generating a data record. Alternatively, the data record may include an identifier for the object and / or the location of the metrology mark. In one embodiment, reference code may be printed on an object that includes data record data and / or may provide a reference for locating and / or accessing the data record data (eg, a mark printer 228). By)). The reference code can be read by the reader device in the lithocell. In one embodiment, the reference code comprises a barcode. Further, the method 400 may optionally include an operation 416 in which the data record is sent from the metrology mark module to the lithographic apparatus and stored in the lithographic apparatus before transferring the pattern to the object within the lithographic apparatus. The lithographic apparatus uses the data in the data record to control its operation using replacement metrology marks.

The method 400 further includes an operation 418 in which the object is measured (eg, aligned) using a replacement metrology mark in the lithographic apparatus. The method 400 further includes an operation 420 in which, by the patterning device, the pattern is transferred to an object (or a film of resist) positioned over the patterning device based on measurements made in the lithographic apparatus using a replacement metrology mark. Include.

In one embodiment, subsequent to the first device lithography step of the device patterning process, measuring the degraded metrology mark on the object and / or device pattern feature associated with the degraded metrology mark, wherein the degraded metrology mark is at least partially As a result from the first device lithography step for the object; And before the second device lithography step of the device patterning process for the object, generating a replacement metrology mark on the object for use in the patterning process instead of the degraded metrology mark. Is provided.

In one embodiment, the method further comprises measuring the replacement metrology mark on the object prior to the second device lithography step using a metrology step. In one embodiment, the method comprises measuring the degraded metrology mark and measuring the degraded metrology mark comprises measuring the degraded metrology mark by a first type of metrology. The measuring of the replacement measurement mark includes measuring the replacement measurement mark by a second type of measurement different from the measurement of the first type. In one embodiment, the method comprises measuring the degraded metrology mark,

Measuring the degraded metrology mark includes measuring the degraded metrology mark by a first type of metrology, and wherein the second device lithography step is of a second type that is different from the first type of metrology. Measure the replacement metrology mark using metrology. In one embodiment, the first type and the second type of measurement are alignment measurements of the first type and the second type. In one embodiment, the first type of metrology includes stack metrology to determine a position error of the degraded metrology mark due to one or more layers of the degraded metrology mark or on the deteriorated metrology mark. In one embodiment, generating the replacement metrology mark includes generating the replacement metrology mark at a predetermined distance offset. In one embodiment, the method further comprises generating a data record for use in the patterning process when measuring the replacement mark, wherein the data record is an identifier of the object and the distance offset of the replacement measurement mark. It includes. In one embodiment, the method includes measuring a position of the degraded metrology mark relative to a device pattern feature, wherein the distance offset comprises the distance offset of the replacement metrology mark relative to the device pattern feature. . In one embodiment, generating the replacement metrology mark includes performing an optical process and / or a physical process on the object. In one embodiment, generating the replacement metrology mark includes generating the replacement metrology mark on the side of the object, such as a degraded metrology mark. In one embodiment, generating the replacement metrology mark includes generating the replacement metrology mark on the side of the object different from the degraded metrology mark. In one embodiment, generating the replacement metrology mark includes adding mark material to the surface of the object. In one embodiment, generating the replacement metrology mark includes removing an object material and / or a portion of the layer of resist on the object. In one embodiment, the degraded metrology mark and replacement metrology mark are alignment marks. In one embodiment, the method further comprises: measuring the replacement metrology mark of the object as part of the second device lithography step; And transferring a pattern to the object based on the measurement of the replacement metrology mark. In one embodiment, transferring the pattern to the object includes performing a photolithography process. In one embodiment, the object is a semiconductor substrate.

In one embodiment, a metrology sensor configured to measure a degraded metrology mark on an object following a first device lithography step of a device patterning process and / or to measure a device pattern feature associated with the degraded metrology mark—the degradation A metrology mark is at least in part resulting from the first device lithography step for the object; And a mark appending device configured to generate a replacement metrology mark on the object prior to any subsequent device lithography step of the device patterning process, wherein the replacement mark is to be used in the patterning process instead of the degraded metrology mark. An apparatus is provided, including.

In one embodiment, the mark adding device is configured to add the replacement mark without adding a device pattern. In one embodiment, the metrology sensor is an alignment sensor configured to determine the position of the degraded metrology mark. In one embodiment, the apparatus is configured to measure the replacement metrology mark according to a second type of mark metrology that is different from the first type of mark metrology used by the metrology sensor to measure the degraded metrology mark. It further includes an additional metrology sensor.

In one embodiment, a first metrology sensor is configured to measure a degraded metrology mark on the object in accordance with a first type of mark metrology; A mark adding device configured to add a replacement metrology mark on the object based on the measurement of the deteriorated mark; And a second measurement sensor configured to measure the replacement measurement mark in accordance with a second type of mark measurement different from the first type of mark measurement.

In one embodiment, the first metrology sensor is configured to measure the degraded metrology mark subsequent to a first device lithography step of a device patterning process for the object, wherein the mark adding device is a device for the object. Configured to add a replacement metrology mark prior to the second device lithography step of the patterning process. In one embodiment, the first type of mark metrology is based on infrared radiation, visible light, ultraviolet radiation, and / or x-ray radiation. In one embodiment, the first type of mark metrology includes scanning electron microscopy, tunneling electron microscopy, atomic force microscopy, confocal microscopy, and / or near field optical microscopy. In one embodiment, the first type and the second type of measurement are alignment measurements of the first type and the second type. In one embodiment, the mark adding device is configured to optically convert the material on the object by removing the object material and / or a portion of the layer of resist on the object by an additional process for the object, and / or And imprinting material onto the object to produce the replacement mark. In one embodiment, the mark adding device is configured to generate the replacement mark at a predetermined distance offset from the degraded measurement mark. In one embodiment, the apparatus further comprises a computer system configured to generate a data record for use in the patterning process when measuring a replacement mark, wherein the data record comprises an identifier of the object and the replacement measurement mark. And the distance offset. In one embodiment, the mark adding device is configured to generate a replacement metrology mark on the face of the object, such as a degraded metrology mark. In one embodiment, the mark adding device is configured to generate a replacement metrology mark on the side of the object different from the degraded metrology mark. In one embodiment, the degraded metrology mark and replacement metrology mark are alignment marks. In one embodiment, the apparatus is configured to measure the replacement metrology mark on the object and transfer a pattern to the object based on the measurement of the replacement metrology mark as part of the lithographic step of the patterning process. It further includes. In one embodiment, the object is a semiconductor substrate.

As will be appreciated by those skilled in the art, the present invention may be embodied as a system, method or computer program product. Correspondingly, aspects of the present invention are generally intended for use in the context of entirely hardware embodiments, generally software embodiments (firmware, resident software, micro-code, etc.), all of which are generally referred to herein as " circuits, " Or a combination of software and hardware aspects. Moreover, aspects of the present invention may take the form of a computer program product implemented on any one or more computer readable medium (s) having computer-usable program code implemented thereon.

Any combination of one or more computer readable medium (s) may be used. The computer readable medium may be a computer readable signal medium or a computer readable storage medium. For example, the computer readable storage medium may be, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, device, or any suitable combination thereof. More specific examples of computer-readable media (non-exhaustive lists) include: electrical connections with one or more wires, portable computer diskettes, hard disks, random access memory (RAM), read-only memory (ROM), erasable programming Possible read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CDROM), optical storage device, magnetic storage device, or any suitable combination thereof. In the context of this document, a computer readable storage medium may be any tangible medium that can contain or store a program for use by or in connection with an instruction execution system, apparatus, or device.

The computer readable signal medium may comprise a propagated data signal in which the computer readable program code is embodied, for example, in baseband or as part of a carrier wave. Such propagated signals may take any of a variety of forms, including but not limited to electromagnetic, optical, or any suitable combination thereof. The computer readable signal medium is not a computer readable storage medium and may be any computer readable medium capable of communicating, propagating, or transmitting a program for use by or in connection with an instruction execution system, apparatus, or device.

Computer code embodied on a computer-readable medium may be implemented using any suitable medium, including but not limited to wireless, wireline, fiber optic cable, radio frequency (RF), or the like, or any suitable combination thereof. May be transmitted.

Computer program code for performing the operations of aspects of the present invention may include conventional procedural programming languages such as Java ™, Smalltalk ™, C ++ or the like and a “C” programming language or the like. May be written in any combination of one or more programming languages, including; The program code may be executed entirely on the user's computer, partly on the user's computer, as a standalone software package, partly on the user's computer and partly on the remote computer, or entirely on the remote computer or server. In the latter scenario, the remote computer may be connected to the user's computer via any type of network, including a local area network (LAN), or a wide area network (WAN), or the connection may be (eg, an Internet service provider). It can also be made to an external computer.

Computer program instructions may also be loaded into a computer, other programmable data processing apparatus, or other device to cause a series of operational steps to be performed on the computer, another programmable device, or another device, thereby creating a computer implemented process. It is also possible for the instructions executed in the apparatus to provide a process for implementing one or more of the functions / acts defined herein.

As mentioned above, the example embodiments may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment that includes both hardware and software elements. In one embodiment, the mechanisms of the example embodiments may be implemented in software or program code, which includes, but is not limited to, firmware, resident software, microcode, and the like.

A data processing system suitable for storing and / or executing program code will include at least one processor coupled directly or indirectly to a memory element via a system bus. The memory element may include local memory employed during actual execution of the program code, bulk storage, and cache memory that provides temporary storage of at least some program code to reduce the number of times that code must be retrieved from the bulk storage during execution. .

Input / output or I / O devices (including but not limited to keyboards, displays, pointing devices, etc.) may be coupled to the system either directly or through intervening I / O controllers. The network adapter may also be coupled to the system such that the data processing system is coupled to another data processing system or remote printer or storage device through an intervening private or public network. Modems, cable modems and Ethernet cards are just some of the types of network adapters currently available.

7 is a block diagram illustrating a computer system 1700 that can help to implement the methods and flows disclosed herein. Computer system 1700 may include a bus 1702 or other communication mechanism for communicating information, and a processor 1704 (or several processors 1704 and 1705) coupled with bus 1702 to process information. Include. Computer system 1700 further includes main memory 1706, such as random access memory (RAM) or other dynamic storage device, coupled to bus 1702 to store information and instructions to be executed by processor 1704. do. Main memory 1806 may also be used to store temporary variables or other intermediate information during the execution of instructions to be executed by processor 1704. Computer system 1700 further includes a read only memory (ROM) 1708 or other static storage device coupled to bus 1702 to store static information and instructions for processor 1704. A storage device 1710, such as a magnetic disk or optical disk, is provided and coupled to the bus 1702 to store information and instructions.

Computer system 1700 may be coupled to display 1712, such as a cathode ray tube (CRT) or flat panel or touch panel display, via bus 1702 to display information to a computer user. Input device 1714, which includes alphanumeric keys and other keys, is coupled to bus 1702 to communicate information and command selections to processor 1704. Another type of user input device is a cursor control 1716, such as a mouse, trackball, or cursor direction key, for communicating indication information and command selections to the processor 1704 and controlling cursor movement on the display 1712. . Such an input device typically has two degrees of freedom in two axes, a first axis (eg x) and a second axis (eg y), allowing the device to specify a position in the plane. A touch panel (screen) display may be used as the input device.

According to one embodiment, some of the processes described herein may be performed by computer system 1700 in response to processor 1704 executing one or more sequences of one or more instructions contained in main memory 1706. have. Such instructions may be read into main memory 1706 from another computer-readable medium, such as storage device 1710. Executing a sequence of instructions contained in main memory 1706 causes processor 1704 to perform the process steps described herein. One or more processors in the multiple processing unit may be employed to execute the sequence of instructions contained in main memory 1706. In other embodiments, wired circuitry may be used instead of or in combination with software instructions. Thus, the description herein is not limited to any particular combination of hardware circuitry and software.

The term "computer-readable medium" refers to any tangible medium that participates in providing instructions to the processor 1704 to be executed when used herein. Such media may take many forms, including but not limited to non-volatile media, volatile media, and transmission media. Non-volatile media includes, for example, optical or magnetic disks, such as storage device 1710. Volatile media includes dynamic memory, such as main memory 1706. Transmission media includes fiber optics, including coaxial cables, copper wiring, and wires including bus 1702. The transmission media may take the form of acoustic or light waves, such as those generated during radio frequency (RF) and infrared (IR) data communications. Common forms of computer-readable media include, for example, floppy disks, flexible disks, hard disks, magnetic tapes, and any other magnetic media, magneto-optical media, CD-ROM, DVD, any other optical media. , Punch card, paper tape, any other physical medium with a pattern of holes, RAM, PROM, and EPROM, FLASH EPROM, any other memory chip or cartridge, carrier to be described below, or any other computer readable Media.

Various forms of computer readable media may be involved in carrying one or more sequences of one or more instructions to the processor 1704 for execution. For example, the instructions may initially be held on a magnetic disk of a remote computer. The remote computer can load the instructions into its dynamic memory and send the instructions over a telephone line using a modem. A modem held locally in computer system 1700 receives data from a telephone line and converts this data into an infrared signal using an infrared transmitter. An infrared detector coupled to the bus 1702 can receive data carried in the infrared signal and load this data onto the bus 1702. Bus 1702 carries data to main memory 1706, which processor 1704 retrieves and executes instructions from. Instructions received from main memory 1706 may optionally be stored in storage device 1710 before or after execution by processor 1704.

Computer system 1700 may further include a communication interface 1718 coupled to bus 1702. The communication interface 1718 provides a two-way data communication coupling to a network link 1720 connected to the local network 1722. For example, communication interface 1718 may be an integrated services digital network (ISDN) card or modem for providing a data communication connection to a corresponding type of telephone line. As another example, communication interface 1718 may be a local area network (LAN) card for providing a data communication connection to a compatible LAN. A wireless link may be implemented. In any such implementation, communication interface 1718 transmits and receives electrical, electromagnetic or optical signals that carry digital data streams representing various types of information.

Network link 1720 typically provides data communication to other data devices via one or more networks. For example, network link 1720 may provide a connection to data equipment operated by host computer 1724 or Internet service provider (ISP) 1726 over local network 1722. ISP 1726 now provides data communication services over a worldwide packet data communication network, now commonly referred to as " Internet 1728 ". Both local network 1722 and the Internet 1728 use electrical, electromagnetic or optical signals that carry digital data streams. Signals passing through various networks and signals passing through a network link 1720 and passing through a communication interface 1718 to carry digital data to or from the computer system 1700 are exemplary forms of carriers for transporting information. admit.

Computer system 1700 may send messages and receive data including program code via network (s), network link 1720, and communication interface 1718. In the example of the Internet, the server 1730 can transmit the requested code for the application program over the Internet 1728, ISP 1726, local network 1722, and communication interface 1718. One application so downloaded may, for example, provide a method or portion thereof as described herein. The received code may be executed by the processor 1704 when received and / or stored in the storage device 1710, or other non-volatile storage, to be executed later. In this manner, computer system 1700 may obtain application code in the form of a carrier wave.

Although particular reference has been made to fabricating ICs herein, it should be clearly understood that the disclosure herein has many other possible applications. For example, the present invention can be employed in the manufacture of integrated optical systems, induction and detection patterns for magnetic domain memories, liquid crystal display panels, thin film magnetic heads, and the like. Those skilled in the art will, in the context of this other application, use of any term such as "reticle" / "mask", "wafer" or "die", respectively, "patterning device", "substrate" and "target portion", respectively. It will be understood that it may be interchangeable with more general terms such as ".

As used herein, the terms "radiation" and "beam" refer to ultraviolet radiation (e.g., radiation having a wavelength of 365, 248, 193, 157 or 126 nm) and EUV (e.g., wavelengths in the range of about 5-100 nm). Is used to cover all types of electromagnetic radiation, including extreme ultraviolet radiation.

Although the concepts disclosed herein may be used in systems and methods for imaging on a substrate such as a silicon wafer, the disclosed concepts may be used in conjunction with any type of lithography system, such as those used for imaging on a substrate other than a silicon wafer. It will be appreciated that it may be used.

In the block diagram, the illustrated components are shown as discrete functional blocks, but embodiments are not limited to systems organized as the functionality described herein is shown. The functionality provided by each of the components may be provided by software or hardware modules organized differently from those shown in the figures, for example such software or hardware may be intermixed, co-coupled, duplicated, separated, distributed (e.g., For example within a data center or geographically), or in other ways. The functionality described herein may be provided by one or more processors of one or more computers executing code stored on a tangible non-transitory machine readable medium. In some cases, third party content delivery networks may host some or all of the information delivered across the networks, in which case the extent to which the information (eg, content) is supplied or otherwise provided This information is provided by sending a command to retrieve the information from the content delivery network.

Unless expressly stated otherwise, as is apparent from this specification, descriptions using terms such as "processing" "calculating" "computing" "determining", or the like throughout the specification, or special-purpose computer or similar special-purpose electronic processing / calculating device It is understood that the term refers to the operation or process of a particular device.

The reader should understand that the present invention describes several inventions. Applicants grouped these inventions into a single document, rather than separating those inventions into a number of individual patent applications, as their related technical subject matter could have their own economics in the filing process. However, the distinct advantages and aspects of these inventions should not be combined. In some cases, the embodiments solve all of the defects not noted herein, but these inventions are independently useful, and some embodiments solve only a subset of these problems or are clearly understood by those skilled in the art upon reviewing the specification. It should be understood that it provides other advantages not mentioned. Because of cost constraints, some of the inventions disclosed herein are not claimed in their current state and may be claimed in subsequent applications, such as continuing applications, or by amending current claims. Similarly, due to space constraints, the abstract and summary sections of the present disclosure should not be considered to include an extensive listing of all such inventions or all aspects of such inventions.

The detailed description and drawings are not intended to limit the invention to the particular forms disclosed, and on the contrary include all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined in the appended claims. It should be understood that it is intended to.

Modifications and alternative embodiments of various aspects of the invention will be apparent to those skilled in the art upon reference to the specification. Accordingly, the detailed description and drawings are to be regarded as illustrative only and to be understood as to teach those skilled in the art the general manner of carrying out the invention. It is to be understood that the forms of the invention shown and described herein are to be regarded as an example of embodiments. As will be apparent to those skilled in the art having the benefit of the present disclosure, elements and materials may be substituted for those illustrated and described herein, parts and processes may be reversed or omitted, and certain features may be independent It may be utilized as, the features of the embodiments or embodiments may be combined. Changes may be made in the elements described herein without departing from the spirit and scope of the invention as described in the claims that follow. Footnotes herein are for the convenience of the organization only and are not meant to limit the scope of the invention.

As used throughout this specification, the word “may” is used in a permissive sense (ie, likelihood), rather than in a compulsory sense (ie, must). The words "comprising", "comprising", "comprising", and the like, mean including, but not limited to. As used throughout this specification, the singular forms "a", "an" and "it" include plural reference members unless the context clearly indicates otherwise. Thus, for example, "an" element or "a" element refers to a combination of two or more elements, although there are different terms and phrases for one or more elements, such as "one or more". Include. The term “or”, unless indicated otherwise, is non-exclusive, ie encompasses both “and” and “or”. Terms describing a conditional relationship, for example, "Y in response to X", "Y for X", "Y for X, Y for Y", "Y for X", etc. Of causal relationships that are the necessary causal condition of, or that the predecessor is a sufficient causal condition, or that the predecessor is the constributory causal condition, for example, "If condition Y is achieved, state X occurs" It is a generic name for "X occurs only" and "X occurs" for Y and Z. This conditional relationship is not limited to the result immediately following the achievement of the predecessor because some results may be delayed, and in conditional statements, the predecessor is associated with the result, for example, Related. The statement that a plurality of attributes or functions are mapped to a plurality of objects (eg, one or more processors that perform steps A, B, C, and D), unless otherwise indicated, all such attributes or functions are Both being mapped to an object and a subset of the attribute or function is mapped to a subset of the attribute or function (e.g., all processors each perform step AD, and processor 1 performs step A and Processor 2 performs part of steps B and C, and processor 3 performs both part of step C and step D). Furthermore, unless stated otherwise, a statement that a value or action is "based" on another condition or value is used when the condition or value is the only factor and when the condition or value is one of several factors. It covers both. Unless indicated otherwise, a statement that "each" instance of some collections has some characteristics should not be interpreted to exclude the case where some of the larger collections' otherwise otherwise identical or similar elements do not have such characteristics. That is, each does not necessarily mean each and all.

With respect to the extent to which certain U.S. patents, U.S. patent applications, or other documents (e.g., materials) are incorporated and incorporated, such U.S. patents, U.S. patent applications, and other documents may be used between such documents and the statements and drawings referred to herein. Incorporated herein by reference to the extent that no conflict exists. In the event of such a conflict, any such conflicting content in such US patents, US patent applications, and other documents incorporated herein by reference is not specifically incorporated herein by reference.

The detailed description herein has been presented for purposes of illustration and description, and is not intended to be exhaustive or to limit the invention in the form disclosed. Many variations and modifications will be apparent to those skilled in the art. Accordingly, it will be apparent to one skilled in the art that changes may be made as described without departing from the scope of the claims set forth below.

Claims (26)

Subsequent to the first device lithography step of the device patterning process, measuring a degraded metrology mark on the object and / or a device pattern feature associated with the degraded metrology mark, wherein the degraded metrology mark is at least partially applied to the object. Originating from said first device lithography step for; And
Prior to a second device lithography step of the device patterning process for the object, generating a replacement metrology mark on the object for use in the patterning process instead of the degraded metrology mark. The method of claim 1,
The method,
Using the metrology step, measuring the replacement metrology mark on the object prior to the second device lithography step. The method of claim 2,
The method comprises measuring the degraded metrology mark,
Measuring the deteriorated metrology mark comprises measuring the deteriorated metrology mark by a first type of metrology,
Measuring the replacement metrology mark comprises measuring the replacement metrology mark by a second type of measurement that is different from the first type of measurement. The method according to any one of claims 1 to 3,
The method comprises measuring the degraded metrology mark,
Measuring the deteriorated metrology mark comprises measuring the deteriorated metrology mark by a first type of metrology,
And the second device lithography step measures the replacement metrology mark using a second type of metrology that is different from the first type of metrology. The method according to claim 3 or 4,
And the first type and second type of measurement are first and second type of alignment measurements. The method according to claim 3 or 4,
The first type of metrology includes stack metrology for determining a positional error of the degraded metrology mark due to one or more layers of the degraded metrology mark or on the degraded metrology mark. . The method according to any one of claims 1 to 6,
Generating the replacement metrology mark comprises generating the replacement metrology mark at a predetermined distance offset. The method of claim 7, wherein
The method,
Generating a data record for use in the patterning process when measuring the replacement metrology mark,
The data record comprises an identifier of the object and a distance offset of the replacement metrology mark. The method according to claim 7 or 8,
The method,
Measuring a position of the degraded metrology mark relative to a device pattern feature,
The distance offset comprises a distance offset of the replacement metrology mark with respect to the device pattern feature. The method according to any one of claims 1 to 9,
Generating the replacement measurement mark,
Performing an optical process and / or a physical process on the object. The method according to any one of claims 1 to 10,
Generating the replacement measurement mark,
Adding a mark material to the surface of the object. The method according to any one of claims 1 to 10,
Generating the replacement measurement mark,
Removing a portion of the object material and / or a layer of resist on the object. The method according to any one of claims 1 to 12,
And the degraded metrology mark and the replacement metrology mark are alignment marks. The method according to any one of claims 1 to 13,
The method,
Measuring the replacement metrology mark of the object as part of the second device lithography step; And
Transferring the pattern to the object based on the measurement of the replacement metrology mark. A metrology sensor configured to measure a degraded metrology mark on an object following a first device lithography step of a device patterning process and / or to measure a device pattern feature associated with the degraded metrology mark, wherein the degraded metrology mark is at least partially As a result from the first device lithography step for the object; And
Prior to any subsequent device lithography step of the device patterning process, a mark adding device configured to generate a replacement metrology mark on the object, wherein the replacement metrology mark is to be used in the patterning process instead of the degraded metrology mark Including, the device. The method of claim 15,
And the mark adding device is configured to add the replacement metrology mark without adding a device pattern. The method according to claim 15 or 16,
The metrology sensor is an alignment sensor configured to determine a position of the degraded metrology mark. The method according to any one of claims 15 to 17,
The device,
And an additional metrology sensor configured to measure the replacement metrology mark in accordance with a second type of mark metrology that is different from the first type of mark metrology used by the metrology sensor to measure the degraded metrology mark. . A first metrology sensor configured to measure a degraded metrology mark on the object in accordance with a first type of mark metrology;
A mark adding device configured to add a replacement metrology mark on the object based on the measurement of the deteriorated metrology mark; And
And a second measurement sensor configured to measure the replacement measurement mark in accordance with a second type of mark measurement different from the first type of mark measurement. The method of claim 19,
The first metrology sensor is configured to measure the degraded metrology mark subsequent to a first device lithography step of a device patterning process for the object,
And the mark adding device is configured to add a replacement metrology mark prior to a second device lithography step of the device patterning process for the object. The method of claim 19 or 20,
And the first type of mark metrology is based on infrared radiation, visible light, ultraviolet radiation, and / or x-ray radiation. The method of claim 19 or 20,
The first type of mark metrology includes scanning electron microscopy, tunneling electron microscopy, atomic force microscopy, confocal microscopy, and / or near field optical microscopy. The method according to any one of claims 15 to 22,
The mark adding device may be adapted to optically convert a material on the object, and / or to convert the material on the object, by removing a portion of the object material and / or a layer of resist on the object by an additional process for the object. By imprinting to generate the replacement metrology mark. The method according to any one of claims 15 to 23,
And the mark adding device is configured to generate the replacement metrology mark at a predetermined distance offset from the degraded metrology mark. The method of claim 24,
The device,
A computer system configured to generate a data record for use in the patterning process when measuring the replacement metrology mark,
The data record includes an identifier of the object and a distance offset of the replacement metrology mark. The method according to any one of claims 15 to 24,
The device,
And a lithographic apparatus configured to measure the replacement metrology mark on the object as part of the lithography step of the patterning process and transfer a pattern to the object based on the measurement of the replacement metrology mark.

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